• Tuberculosis
• Infection Control

TB incidence may be finally falling in England; 6520 cases were notified in 2014 giving an estimated annual incidence of 12/100 000.1 There has been a year-on-year decrease in notified cases since 2011, but TB incidence in England still remains unacceptably high and in excess of most European Union countries.2 A strategy to reduce and eventually eliminate TB as a public health problem was released by Public Health England (PHE) and National Health Service England in 2015.3 It identifies 10 areas where improvements in current practice can improve TB control, which include ensuring comprehensive contact tracing, tackling TB in underserved populations, systematic implementation of new entrant latent TB screening, strengthening surveillance and monitoring and providing universal access to high-quality diagnostics.

The introduction of routine genetic testing of cultured TB isolates in 2010 by PHE has the potential to improve our understanding of each of these challenges. In Thorax, Hamblion et al use data from 2010 to 2012 to provide some insight into TB transmission in London, the unofficial TB capital of Europe and home to approximately 40% of TB cases in England.4

The methodology using 24 loci mycobacterial interspersed repetitive units–variable number of tandem repeats (MIRU–VNTR) typing has been well validated.5 TB cases were classed as clustered if they matched to another case on at least 23 typed loci. Clustered cases were compared …